The perforation of petroleum producing wells is realized by lowering into the well various metallic perforating-guns of different lengths, whose respective charge carriers are charged with shaped charges, connected by joints and fired in a vertical fashion, one after another, resulting in a single unit of joined perforating-guns for the perforation of various zones, in a single lowering.
The shaped charges are explosives set in such a manner that they concentrate the force of the explosion outward, generating a jet of gas (plasma) at high pressure and temperature, that pulls the metal from the interior of the charge and projects it outward until it arrives at the well formation, with this action the charges produce a perforating effect that is variable in proportion to the potency of the charges.
Perforating guns are detonated one at a time beginning from the bottom and continuing in an upward fashion. After each detonation, the gun assembly is repositioned vertically in such a way that the lowest gun that remains active is located at the desired depth of perforation.
To fulfill the operation so briefly described, while simultaneously respecting existing norms for the manipulation of explosive, highly capable operators are required to connect and assemble the guns and the wellhead, stripping the ends of connecting wires and joining them by twisting the exposed end of the wires together and covering the joint with adhesive electrical-tape, resulting in an artisanal process that requires extreme caution. It should be noted that petroleum production and exploration activities are generally located in areas with hostile climate conditions for the operators; work hours are assigned in accordance to the needs of the operation and may include night and daytime hours with extreme cold or heat, rain or wind, darkness or sunlight; hours are controlled by working against the clock and by penalizing setbacks; to that respect, it is absolutely necessary that the strictest safety norms be followed while handling explosive material; all of these factors together contribute to an increased likelihood that operators may commit errors while wiring or assembling the perforating guns to be introduced into the well.
From the above facts, there exists an obvious need to simplify the operation of putting together and assembling the perforating gun assembly, in other words, simplification of the mechanical assembly and electrical connections of the gun assembly to establish the required firing sequence. The object of the presented invention deals with the means to perform the mechanical connection of the gun assembly.
Currently, perforating guns are connected and assembled using a multitude of diverse connectors that are consecutively tied together via threaded union pieces, or tandems, resulting in an onerous task requiring a variety of accessories and pieces that constitutes a significant difficulty in the connection and assembly of said guns.